<!DOCTYPE html>
<html lang="en">

<head>
  <title>3列布局</title>
</head>

<body>
  <style>
    /* 为了方便查看，给布局容器设置高度和颜色 */
    .main, .left, .right {
      height: 100px;
    }
    .main {
      background-color: rgb(214, 137, 114);
    }
    .left {
      background-color: rgb(247, 228, 166);
    }
    .right {
      background-color: rgb(216, 243, 155);
    }
  </style>
  <div class="wrap">
    <main class="main">main</main>
    <aside class="left">left</aside>
    <aside class="right">right</aside>
  </div>
</body>

</html>